A student looks at cells from an onion root tip under a microscope.
The student counts 1200 cells. In 48 of the cells, the chromosomes are moving apart.
One cell cycle in these cells takes 25 hours.
Assume that the proportion of cells seen at a stage is proportional to the time spent in that stage.
Estimate the time spent on movement of chromosomes in each cell cycle.
0.040.040.04 hours
1.01.01.0 hours
4.04.04.0 hours
252525 hours
194 exam-style questions on OCR GCSE Biology 2.1 Supplying the cell, covering 2.1.1 Transport across cell membranes, 2.1.2 Mitosis and the cell cycle, 2.1.3 Importance of cell differentiation, and 2.1.4 Stem cells. Each one has a worked solution and a mark scheme showing where the marks go.